Tensile Testing of Metals Proficiency Testing...

REPORT NO. 901

Tensile Testing of Metals

Proficiency Testing Program

Round 7

March 2015

ACKNOWLEDGMENTS

PTA wishes to gratefully acknowledge the technical assistance provided for this program by Mr K Bazley, BlueScope Steel Limited, Port Kembla. PTA also wishes to thank Mr W Robinson and Mr G Pownall, ARL Laboratory Services Pty Ltd, for the supply and homogeneity testing of the samples.

© COPYRIGHT PROFICIENCY TESTING AUSTRALIA 2015

PO Box 7507 Silverwater NSW 2128 AUSTRALIA

CONTENTS

1. FOREWORD 1

2. FEATURES OF THE PROGRAM 1

3. FORMAT OF THE APPENDICES 2

4. DESIGN OF THE PROGRAM 2

5. OUTLIER RESULTS 2

Table A: Summary Statistics for All Tests 3

Table B: Summary of Statistical Outliers 4

6. PTA AND TECHNICAL ADVISER'S COMMENTS 4

7. REFERENCES 8 APPENDICES

APPENDIX A

Summary of Results

0.2% Proof Stress A1.1

Tensile Strength A2.1

Percentage Elongation after Fracture A3.1

Percentage Reduction in Area after Fracture A4.1

Method Information and Other Reported Results A5.1

APPENDIX B

Homogeneity Testing B1.1

APPENDIX C

Instructions to Participants C1.1

Results Sheet C2.1

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1. FOREWORD This report summarises the results of a proficiency testing program on the

tensile properties of metals. It constitutes the seventh round of an ongoing series of programs.

Proficiency Testing Australia (PTA) conducted the testing program in

December 2014 / January 2015. The aim of the program was to assess laboratories' ability to competently perform the nominated tests.

The Program Coordinator was Dr M Bunt. The Technical Adviser was Mr K

Bazley, BlueScope Steel Limited, Port Kembla. This report was authorised by Mrs F Watton, PTA Quality – Business Development Manager.

2. FEATURES OF THE PROGRAM (a) A total of 19 laboratories participated in the program, all of which returned

results for inclusion in the final report. Laboratories from the following countries received samples:

11 AUSTRALIA 1 COLOMBIA 1 ENGLAND 1 HONG KONG 1 ITALY 1 MEXICO 1 NEW ZEALAND 1 SINGAPORE 1 USA

To ensure confidential treatment of results, each laboratory was allocated a unique code number. All reference to participants in this report is by allocated code numbers. Please note that one laboratory reported more than one set of results and, therefore, the code number for this laboratory (with letter) could appear several times in the same data set.

(b) The results reported by participants are presented in Appendix A.

(c) Laboratories were provided with a steel flat bar sample and a steel round bar sample. Both samples were approximately 300 mm in length. The flat bar sample was approximately 50 mm in width and 5 mm in thickness. The round bar sample was approximately 19 mm in diameter. Laboratories were asked to perform tests for:

0.2% Proof Stress (non-proportional elongation) (Rp0.2);

Tensile Strength (Rm);

Percentage Elongation after Fracture (A%); and

Percentage Reduction in Area after Fracture (Z%).

(d) All testing, recording and reporting was to be performed in accordance with the laboratory’s routine test methods, but testing in accordance with AS 1391 or ISO 6892-1 were the preferred test methods.

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(e) Laboratories were requested to perform the tests according to the Instructions to Participants provided and to record the results, along with an estimate of their measurement uncertainty (MU) for each result, on the accompanying Results Sheet, which was distributed with the samples. Copies of these documents appear in Appendix C.

(f) Prior to distribution, the samples were tested for homogeneity by ARL

Laboratory Services Pty Ltd. Based on the results of this testing, the homogeneity of the samples was established (see Appendix B).

3. FORMAT OF THE APPENDICES (a) Appendix A is divided into five sections (A1-A5).

Sections A1-A4 contain the analysis of results reported by laboratories for 0.2% Proof Stress (non-proportional elongation) (Rp0.2), Tensile Strength (Rm), Percentage Elongation after Fracture (A%) and Percentage Reduction in Area after Fracture (Z%). These sections contain, where appropriate: i) a table of results reported by laboratories for each test, with estimates of

their MUs and calculated z-scores; ii) a listing of the summary statistics; and iii) ordered z-score charts.

Section A5 contains information on the methods used by laboratories and the results reported by laboratories for Tensile Specimen Thickness / Diameter, Tensile Specimen Width, Tensile Specimen Gauge Length, Elastic Stress or Strain Rate and Plastic Strain Rate.

(b) Appendix B contains details of the homogeneity testing. (c) Appendix C contains copies of the Instructions to Participants and Results

Sheet.

4. DESIGN OF THE PROGRAM

For each statistically analysed test, robust statistical procedures were used to generate the z-scores and summary statistics for each sample - number of results, median, normalised interquartile range (IQR), uncertainty of the median, robust coefficient of variation (CV), minimum, maximum and range.

5. OUTLIER RESULTS

Robust z-scores have been used to assess each laboratory’s testing performance. When calculated from single results, z-scores are used to detect excessively high or excessively low results in comparison to the consensus value (the median). Any result with an absolute z-score greater than or equal to three (i.e. ≤ -3.0 or ≥ 3.0) is classified as an outlier. For further details on the calculation and interpretation of robust z-scores, please see the Guide to Proficiency Testing Australia (2014).

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The following table summarises the results submitted by participants for the program.

Table A: Summary Statistics for All Tests

Test Summary Statistics Sample 1 Sample 2

0.2% Proof Stress (non-proportional elongation) (Rp0.2)

(MPa)

Number of Results 20 17

Median 342.0 578.0

Normalised IQR 41.9 12.6

Uncertainty (Median) 11.7 3.8

Tensile Strength (Rm) (MPa)


Median 588.5 621.0



Percentage Elongation after Fracture

(A%)


Median 59.3 13.9



Percentage Reduction in Area after Fracture

(Z%)

Number of Results 17

Median 54.0

Normalised IQR 2.2

Uncertainty (Median) 0.7

Notes: 1. For each test, the results for all test methods were pooled for analysis.

2. The uncertainty of the median was calculated as:n

normIQR

2.

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Table B: Summary of Statistical Outliers (by laboratory code number)

Test Sample 1 Sample 2

0.2% Proof Stress 11 -

Tensile Strength - -


4, 17 11, 17


4, 15

Note: Summary statistics and z-scores for Percentage Elongation after Fracture were calculated by converting the results to a proportional gauge length.

6. PTA AND TECHNICAL ADVISER’S COMMENTS

Consensus values (medians), derived from participants’ results, are used as the assigned values in this program. These values are not metrologically traceable to an external reference. The summary statistics, uncertainties of the assigned values and outliers, for each of the tests, are reported in Tables A and B above. Complete details of the statistical analyses appear in Appendix A.

6.1 Return rate

All 19 of the laboratories that participated in the program returned results. Of these laboratories, the return rate for all tests was as follows:

Test Sample 1 Sample 2

0.2% Proof Stress 19 out of 19 (100%) 17 out of 19 (89%)

Tensile Strength 19 out of 19 (100%) 17 out of 19 (89%)


19 out of 19 (100%) 17 out of 19 (89%)


17 out of 19 (89%)

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6.2 Performance summary

One or more statistical outliers were reported by four laboratories (21%) for this round of the Tensile Testing of Metals program. For comparison, 35% of the participants reported outlier results in Round 6 of the Tensile Testing of Metals program (see Report No. 875 for more details). A total of 128 results were analysed in this round of the program. Of these results, seven (5%) were outliers. For comparison, 6% of the results analysed in Round 6 of the Tensile Testing of Metals program were outliers (see Report No. 875 for more details).

6.3 0.2% Proof Stress

A total of 19 laboratories tested the samples for 0.2% Proof Stress. All of these laboratories tested sample 1, while 17 of these laboratories tested sample 2. Of these 19 laboratories, ten laboratories tested using AS 1391, five laboratories tested using ISO 6892-1, one laboratory used both AS 1391 and ISO 6892-1, two laboratories used ASTM E8 and one laboratory used a method equivalent to ASTM A370 (see Appendix A5 for more details). The methods were pooled when analysing the results for both samples. One laboratory (code 11) reported an outlier for sample 1. There were no outliers reported for sample 2. The robust CV for the 0.2% Proof Stress results for sample 1 was 12.2%. This value is higher than the robust CV of 6.1% obtained for the 0.2% Proof Stress results for the steel flat bar used in Round 6 of this program (see Report No. 875). The last round of the Tensile Testing of Metals program where participants tested a steel round bar for 0.2% Proof Stress was Round 2. The robust CV for the 0.2% Proof Stress results for sample 2 this round was 2.2%. This value is slightly higher than the robust CV of 1.6% obtained for the 0.2% Proof Stress results for the steel round bar used in Round 2 of this program (see Report No. 649). Sixteen laboratories reported measurement uncertainties associated with their 0.2% Proof Stress test results in this round.

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6.4 Tensile Strength

A total of 19 laboratories tested the samples for Tensile Strength. All of these laboratories tested sample 1, while 17 of these laboratories tested sample 2. Of these 19 laboratories, nine laboratories tested using AS 1391, five laboratories tested using ISO 6892-1, one laboratory used both AS 1391 and ISO 6892-1, two laboratories used ASTM E8 and one laboratory used a method equivalent to ASTM A370. One laboratory did not specify the method that they used for testing (see Appendix A5 for more details). The methods were pooled when analysing the results for both samples. There were no outliers reported for either sample. The robust CV for the Tensile Strength results for sample 1 was 2.3%. This value compares well with the robust CVs of 2.1% and 1.5% obtained for the Tensile Strength results for the two steel flat bars used in Round 6 of this program (see Report No. 875). The robust CV for the Tensile Strength results for sample 2 was 1.4%. This value is slightly lower than the robust CVs of 1.9% and 2.2% obtained for the Tensile Strength results for the two steel round bars used in Round 5 of this program (see Report No. 823). Sixteen laboratories reported measurement uncertainties associated with their Tensile Strength test results in this round.

6.5 Percentage Elongation after Fracture

A total of 19 laboratories tested the samples for Percentage Elongation after Fracture. All of these laboratories tested sample 1, while 17 of these laboratories tested sample 2. Of these 19 laboratories, eight laboratories tested using AS 1391, five laboratories tested using ISO 6892-1, one laboratory used both AS 1391 and ISO 6892-1, two laboratories used ASTM E8 and one laboratory used a method equivalent to ASTM A370. Two laboratories did not specify the method that they used for testing (see Appendix A5 for more details). Because the participants employed different width and diameter specimens and different gauge lengths for their tensile testing in this program, it was necessary to convert the Percentage Elongation after Fracture results submitted by the participants to a proportional gauge length. The results, converted to a proportional gauge length, are displayed in Appendix A3, while the formulas used to convert the results are given on page A3.1 of Appendix A3. The methods were pooled when analysing the results for both samples.

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One laboratory (code 17) reported outliers for both samples. One laboratory (code 4) reported an outlier for sample 1. One laboratory (code 11) reported an outlier for sample 2. Laboratory 17 have investigated their outlier results and have informed PTA that they reported Percentage of Plastic Elongation at Maximum Force, instead of Percentage Elongation after Fracture. The robust CV for the Percentage Elongation after Fracture results for sample 1 was 6.4%. This value is slightly lower than the robust CVs of 7.0% and 7.9% obtained for the Percentage Elongation after Fracture results for the two steel flat bars used in Round 6 of this program (see Report No. 875). The robust CV for the Percentage Elongation after Fracture results for sample 2 was 10.0%. This value compares well with the robust CVs of 8.4% and 11.6% obtained for the Percentage Elongation after Fracture results for the two steel round bars used in Round 5 of this program (see Report No. 823). Fifteen laboratories reported measurement uncertainties associated with their Percentage Elongation after Fracture test results in this round.

6.6 Percentage Reduction in Area after Fracture

A total of 17 laboratories tested the samples for Percentage Reduction in Area after Fracture. Of these 17 laboratories, eight laboratories tested using AS 1391, three laboratories tested using ISO 6892-1, one laboratory used both AS 1391 and ISO 6892-1, one laboratory used ASTM E8 and one laboratory used a method equivalent to ASTM A370. Three laboratories did not specify the method that they used for testing (see Appendix A5 for more details). The methods were pooled when analysing the results. Two laboratories (codes 4 and 15) reported outliers. Laboratory 15 have investigated their outlier result and have informed PTA that they reported the final cross-sectional area, instead of Percentage Reduction in Area after Fracture. The robust CV for the Percentage Reduction in Area after Fracture results was 4.1%. This value is higher than the robust CVs of 2.3% and 2.1% obtained for the Percentage Reduction in Area after Fracture results for the two steel round bars used in Round 5 of this program (see Report No. 823). Twelve laboratories reported measurement uncertainties associated with their Percentage Reduction in Area after Fracture test results in this round.

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6.7 Measurement Uncertainty (MU) Some laboratories have not reported any MU estimates for their results this round. These laboratories should follow an approach, such as that described in AS 1391 Appendix H, “An Error Budget”, to the estimation of the MU in tensile testing. Laboratory 17 have informed PTA that they reported their standard MU, rather than their expanded MU. Their reported MU results should therefore be multiplied by the coverage factor k = 2.

6.8 Other Reported Results

In addition to reporting results for 0.2% Proof Stress, Tensile Strength, Percentage Elongation after Fracture and Percentage Reduction in Area after Fracture, participants were also asked to report the Tensile Specimen Thickness / Diameter, Tensile Specimen Width, Tensile Specimen Gauge Length, Elastic Stress or Strain Rate and Plastic Strain Rate. The details reported by each of the participants are displayed in Appendix A5. The information reported is limited, but it was requested in the hope that it would assist in the analysis of the results, especially in converting the Percentage Elongation after Fracture results to a proportional gauge length. There was a large range in the stress and strain rates reported by the participants in this round of the program and many of these results were reported in unusual units. The range of test conditions and test pieces (allowed by the standards), along with test setups, will always allow for variation in the test results obtained.

7. REFERENCES

1. Guide to Proficiency Testing Australia (2014). (This document is located on the PTA website at www.pta.asn.au under Programs / Documents).

2. AS 1391 (2007) – Metallic materials – Tensile testing at ambient

temperature.

3. ISO 6892-1 (2009) – Metallic materials – Tensile testing – Part 1: Method of test at room temperature.

4. ASTM E8 – Standard Test Methods for Tension Testing of Metallic Materials.

5. ASTM A370 – Standard Test Methods and Definitions for Mechanical Testing of Steel Products.

APPENDIX A

Summary of Results

Section A1

0.2% Proof Stress

A1.1

0.2% Proof Stress (non-proportional elongation) (Rp0.2) (MPa) – Results and Z-Scores

Lab Code Sample 1 Sample 2

Result MU (±) Z-Score Result MU (±) Z-Score

1 297 3.52 -1.07 586 2.45 0.63

2 294 8 -1.15 574 15 -0.32

3 252 0.91 -2.15 397* 0.91 ----

4 436 0.10% 2.24 598 0.08% 1.59

5 357 0.02 0.36 580 0.06 0.16

6A 307 14 -0.84 569 26 -0.71

6B 302 10 -0.96 578 19 0.00

7 376 7.97 0.81 - - ----

8 345 28 0.07 - - ----

9 339 6.8 -0.07 573 9 -0.40

10 359 0.04 0.41 575 0.09 -0.24

11 606 17.87 6.30 § 574 16.93 -0.32

12 339 4.0 -0.07 590 8.1 0.95

13 345 1 0.07 590 2 0.95

14 427 3 2.03 580 3 0.16

15 372 3.78 0.72 590 6.00 0.95

16 315 - -0.64 562 - -1.27

17 302 3.36 -0.96 566 4.43 -0.95

18 356 - 0.33 569 - -0.71

19 330 - -0.29 590 - 0.95

Summary Statistics

Statistic Sample 1 Sample 2


Median 342.0 578.0



Robust CV 12.2% 2.2%

Minimum 252 562

Maximum 606 598

Range 354 36

A1.2

Notes:

1. § denotes an outlier (i.e. |z-score| ≥ 3.0). 2. * Laboratory 3 tested the full section of the round bar (sample 2), as per their

normal practice (AS 3679.1). The sample failed in the jaws, perhaps due to deformation of the sample. A second round bar sample was requested for testing. This sample also failed, using alternate grips. Their results for sample 2 have not been analysed.

3. Laboratory 4 reported that there was no definitive indicator from which their software would normally calculate the yield point for 0.2% Proof Stress for sample 1. As a result, a calculation was made to obtain a theoretical yield point.

3

2 1 6B 17

6A 1

6

19

9

12

8 13 1

8

5 10

15 7

14 4

11

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

0.2% Proof Stress (non-proportional elongation) (Rp0.2) - Sample 1

16

17 1

8

6A

9 2

11 10

6B 5 14

1

12

13

15

19

4

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

0.2% Proof Stress (non-proportional elongation) (Rp0.2) - Sample 2

Section A2

Tensile Strength

A2.1

Tensile Strength (Rm) (MPa) – Results and Z-Scores


Result MU (±) Z-Score Result MU (±) Z-Score

1 577 2.45 -0.84 613 2.45 -0.90

2 590 11 0.11 620 12 -0.11

3 578 0.64 -0.77 590* 0.64 ----

4 600 0.08% 0.84 627 0.07% 0.67

5 599 0.03 0.77 621 0.08 0.00

6A 585 7 -0.26 621 8 0.00

6B 586 5 -0.18 620 5 -0.11

7 587 3.6 -0.11 - - ----

8 627 24 2.81 - - ----

9 598 9.4 0.69 612 9.1 -1.01

10 590 0.14 0.11 626 0.15 0.56

11 614 18.11 1.86 633 18.67 1.35

12 585 6.9 -0.26 627 8.6 0.67

13 583 2 -0.40 614 2 -0.79

14 616 3 2.01 615 2 -0.67

15 604 6.16 1.13 637 6.48 1.80

16 579 - -0.69 601 - -2.25

17 576 3.45 -0.91 628 4.43 0.79

18 581 - -0.55 626 - 0.56

19 605 - 1.20 630 - 1.01

Summary Statistics



Median 588.5 621.0



Robust CV 2.3% 1.4%

Minimum 576 601

Maximum 627 637

Range 51 36

A2.2

Note:

1. * Laboratory 3 tested the full section of the round bar (sample 2), as per their normal practice (AS 3679.1). The sample failed in the jaws, perhaps due to deformation of the sample. A second round bar sample was requested for testing. This sample also failed, using alternate grips. Their results for sample 2 have not been analysed.

17 1 3 1

6 18 13 6A 12

6B 7

2 10

9 5 4

15 19

11 14

8

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

Tensile Strength (Rm) - Sample 1

16

9 1 13 14

2

6B

5 6A

10

18 4 12 17 1

9

11

15

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

Tensile Strength (Rm) - Sample 2

Section A3


A3.1

Percentage Elongation after Fracture (A%) – Results and Proportional Gauge Length (PGL) Results


Result MU (±) PGL Result Result MU (±) PGL Result

1 62 0.05 62 11 0.05 11

2 64 1.3 64 14 0.3 14

3 47 0.15 67 * - -

4 61 - 83 11.82 - 12

5 53 0.02 55 14 0.02 14

6A 54 4 62 13 1 13

6B 52 2 59 13 1 13

7 49.8 1.8 57 - - -

8 69 3 58 - - -

9 58 4.0 58 13.2 1 13

10 59 0.03 61 14 0.02 14

11 48.8 0.25 51 32 0.25 29

12 63 0.02 63 14 0.02 14

13 57 1 57 11 1 11

14 45 1 62 9 1 12

15 55 0.38 57 14 0.38 14

16 57 - 59 14 - 14

17 41 0.29 42 7 0.29 7

18 49 - 49 14 - 14

19 54 - 62 14 - 14

Notes:

1. * Laboratory 3 did not report a result for sample 2 as the sample failed (outside

the gauge area). 2. To analyse the Percentage Elongation after Fracture results, the results

submitted by participants were converted to a proportional gauge length (PGL) using the formula:

for the flat bar sample (sample 1) and the formula:

for the round bar sample (sample 2).

0.4

2

Result Tensile Specimen Gauge LengthPGL Result =

2 Diameter

2

0.4

Result Tensile Specimen Gauge LengthPGL Result =

2 Thickness Tensile Specimen Width

A3.2

Percentage Elongation after Fracture (A%) – Proportional Gauge Length (PGL) Results and Z-Scores


PGL Result Z-Score PGL Result Z-Score

1 62 0.67 11 -2.11

2 64 1.17 14 0.04

3 67 2.06 - ----

4 83 6.39 § 12 -1.54

5 55 -1.10 14 0.04

6A 62 0.61 13 -0.70

6B 59 0.01 13 -0.69

7 57 -0.68 - ----

8 58 -0.40 - ----

9 58 -0.27 13 -0.54

10 61 0.55 14 0.00

11 51 -2.22 29 10.90 §

12 63 0.98 14 0.03

13 57 -0.71 11 -2.13

14 62 0.63 12 -1.31

15 57 -0.62 14 0.07

16 59 -0.01 14 0.04

17 42 -4.71 § 7 -5.00 §

18 49 -2.72 14 0.04

19 62 0.66 14 0.02

Summary Statistics



Median 59.3 13.9



Robust CV 6.4% 10.0%

Minimum 42 7

Maximum 83 29

Range 42 22

Note:

1. § denotes an outlier (i.e. |z-score| ≥ 3.0).

A3.3

17 1

8

11

5

13 7 15

8

9 16

6B

10 6A

14 19

1

12 2

3

4

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

Percentage Elongation after Fracture (A%) - Sample 1

17

13 1

4

14

6A 6B

9

10

19

12

16

5 18

2 15

11

-3

-2

-1

0

1

2

3

Ro

bust

Z-S

co

re

Laboratory Code

Percentage Elongation after Fracture (A%) - Sample 2

Section A4


A4.1

Percentage Reduction in Area after Fracture (Z%) – Results and Z-Scores

Lab Code Sample 2

Result MU (±) Z-Score

1 57 0.05 1.35

2 55 1.0 0.45

3 46* 0.52 ----

4 41.0 - -5.85 §

5 58 0.02 1.80

6A 52 1 -0.90

6B 54 1 0.00

9 52 - -0.90

10 55 0.02 0.45

11 48 0.25 -2.70

12 58 0.01 1.80

13 52 2 -0.90

14 51 1 -1.35

15 34 0.38 -8.99 §

16 54 - 0.00

17 53 1.31 -0.45

18 58 - 1.80

19 55 - 0.45

Summary Statistics

Statistic Sample 2

Number of Results 17

Median 54.0

Normalised IQR 2.2

Uncertainty (Median) 0.7

Robust CV 4.1%

Minimum 34

Maximum 58

Range 24

A4.2

Notes:

1. § denotes an outlier (i.e. |z-score| ≥ 3.0). 2. * Laboratory 3 tested the full section of the round bar (sample 2), as per their

normal practice (AS 3679.1). The sample failed in the jaws, perhaps due to deformation of the sample. A second round bar sample was requested for testing. This sample also failed, using alternate grips. Their results for sample 2 have not been analysed.

15 4

11

14

6A 9

13

17

6B

16

2 10

19

1

5 12

18

-3

-2

-1

0

1

2

3

Robust

Z-S

core

Laboratory Code

Percentage Reduction in Area after Fracture (Z%) - Sample 2

Section A5

Method Information and Other Reported Results

A5.1

Method Information

Lab Code 0.2% Proof Stress Tensile Strength

1 ISO 6892 / AS 1391 ISO 6892 / AS 1391

2 AS 1391 - 2007 AS 1391 - 2007

3 AS 1391 AS 1391

4 AS 1391 AS 1391

5 AS 1391 - 2007 AS 1391 - 2007

6A ISO 6892-1 ISO 6892-1

6B ISO 6892-1 ISO 6892-1

7 ISO 6892 ISO 6892

8 ASTM E8 ASTM E8

9 6892-1 6892-1

10 AS 1391 - 2007 AS 1391 - 2007

11 ASTM E8 ASTM E8

12 ISO 6892-1 ISO 6892-1

13 AS 1391 AS 1391

14 NTC 3353/97 NUM 13.2.1 NTC 3353/97 NUM 13.3

15 AS 1391 AS 1391

16 AS 1391 AS 1391

17 ISO 6892-1 ISO 6892-1

18 AS 1391 AS 1391

19 AS 1391 -

A5.2

Method Information

Lab Code Percentage Elongation after Fracture Percentage Reduction in Area after

Fracture

1 ISO 6892 / AS 1391 ISO 6892 / AS 1391

2 AS 1391 - 2007 AS 1391 - 2007

3 AS 1391 AS 1391

4 - -

5 AS 1391 - 2007 AS 1391 - 2007

6A ISO 6892-1 ISO 6892-1

6B ISO 6892-1 ISO 6892-1

7 ISO 6892 -

8 ASTM E8 -

9 6892-1 -

10 AS 1391 - 2007 AS 1391 - 2007

11 ASTM E8 ASTM E8

12 ISO 6892-1 ISO 6892-1

13 AS 1391 AS 1391

14 NTC 3353/97 NUM 13.4 NTC 3353/97 NUM 13.5

15 AS 1391 AS 1391

16 AS 1391 AS 1391

17 ISO 6892-1 ISO 6892-1

18 AS 1391 AS 1391

19 - -

A5.3

Tensile Specimen Thickness / Diameter

Lab Code

Tensile Specimen Thickness (mm) Tensile Specimen Diameter (mm)

Sample 1 Sample 2

Result MU (±) Result MU (±)

1 5.17 0.014 12.46 0.014

2 5.17 0.04 9.98 0.07

3 5.24 0.006 19.0 0.006

4 5.24 - 10.03 -

5 5.12 0.02 9.99 0.02

6A 5.17 0.03 10.05 0.01

6B 5.16 0.02 10.03 0.01

7 5.19 0.001 - -

8 5.18 0.005 - -

9 25.1 0.01 12.01 0.01

10 5.14 0.02 10.09 0.03

11 5.17 0.025 12.59 0.025

12 5.13 0.006 10.01 0.006

13 5.18 0.01 10.05 0.01

14 5.18 0.06 18.98 0.04

15 5.17 0.06 9.91 0.06

16 5.15 1% 19.00 1%

17 5.25 0.0054 10.05 0.0045

18 5.08 - 13.78 -

19 5.11 - 10.05 -

A5.4

Tensile Specimen Width and Tensile Specimen Gauge Length

Lab Code

Tensile Specimen Width (mm) Tensile Specimen Gauge Length (mm)

Sample 1 Sample 1 Sample 2

Result MU (±) Result MU (±) Result MU (±)

1 12.40 0.014 45.0 0.030 62.50 0.030

2 12.52 0.09 45 0.5 50 0.5

3 40.30 0.006 200 0.53 100 0.53

4 49.87 - 200 - 50 -

5 12.50 0.02 50 0.02 50 0.02

6A 20.03 0.03 80 0.02 50 0.02

6B 20.03 0.02 80 0.02 50 0.02

7 20.08 0.01 80.00 0.01 - -

8 38.13 0.01 51 0.01 - -

9 5.13 0.01 65 0.05 60 0.05

10 12.46 0.02 50 0.02 50 0.02

11 12.40 0.025 50.40 0.025 49.75 0.025

12 15.22 0.006 50 0.02 50 0.02

13 12.64 0.01 45 1 50 1

14 49.96 0.05 200 1 200 1

15 12.68 0.06 50 0.29 50 0.29

16 12.49 1% 50 1% 95 1%

17 20.08 0.024 60 0.29 50 0.29

18 19.9 - 57 - 69 -

19 19.97 - 80 - 50 -

A5.5

Elastic Stress or Strain Rate (number / sec)



1 0.00004 - 0.0001 -

2 0.0008 0.000012 0.0008 0.000052

3 22 MPa/s 1.6 MPa/s 11 MPa/s 1.6 MPa/s

4 48 - 60 -

5 20 MPas-1 - 20 MPas-1 -

6A 0.00025 - 0.00025 -

6B 0.00248 - 0.000248 -

7 0.0008 - - -

8 0.001 - - -

9 15 N/mm2 - 15 N/mm2 -

10 20 MPas-1 - 20 MPas-1 -

11 1kN/sec - 1kN/sec -

12 0.00025 - 0.00025 -

13 15MPa - 15MPa -

14 - - - -

15 0.02% / s 0.38% 0.02% / s 0.38%

16 45 - 23 -

17 15 MPa/s - 15 MPa/s -

18 0.001 - 0.001 -

19 10 - 10 -

A5.6

Plastic Strain Rate (number / sec)



1 0.0001 - 0.0002 -

2 0.0024 0.000052 0.0024 0.000052

3 - - - -

4 0.0072 - 0.0082 -

5 0.0008 - 0.0008 -

6A 0.0067 - 0.0067 -

6B 0.0067 - 0.0067 -

7 0.0075 - - -

8 0.001 - - -

9 0.25 mm - 0.25 mm -

10 0.0008 - 0.0008 -

11 1kN/sec - 1kN/sec -

12 0.002 - 0.0067 -

13 0.0022 - 0.0026 -

14 - - - -

15 0.25 mm/s 0.38% 0.25 mm/s 0.38%

16 0.007 - 0.005 -

17 - - - -

18 7.5 MPa/s - 4.0 MPa/s -

19 3 - 3 -

APPENDIX B

Homogeneity

Testing

B1.1

HOMOGENEITY TESTING Before the test pieces were distributed to participants, ten specimens from each sample were selected at random and tested by ARL Laboratory Services Pty Ltd. This was done to assess the variability of the samples to be used in the program. The results of this testing appear in the following tables.

Homogeneity Testing Results

Sample 1 – Flat Bar

Sample Number

Cross-sectional

Area (mm2)

Tensile Strength (MPa)

0.2% Proof Stress (MPa)

Original Gauge Length (mm)

Final Gauge Length (mm)

% Elongation

1-5 194.5 610 365 50 81.9 64

1-12 203.3 605 380 50 82.8 65.5

1-15 203.8 610 370 50 † †

1-21 203.3 595 355 50 81.8 63.5

1-26 202.8 600 360 50 81.5 63

1-31 184.6 605 365 50 80.1 60

1-34 194 605 360 50 81.5 63

1-41 199.2 600 365 50 81.8 63.5

1-46 195.5 600 365 50 81.1 63

1-50 192.9 600 365 50 81.4 63


Sample 2 – Round Bar

Sample Number

Cross-sectional

Area (mm2)

Tensile Strength (MPa)

0.2% Proof Stress (MPa)

Original Gauge Length (mm)

Final Gauge Length (mm)

% Elongation

2-7 283.8 595 570 95.2 107.8 13

2-11 283.8 595 570 95.2 108.9 14.5

2-14 283.8 ‡ ‡ 95.2 108.5 14

2-23 283.8 595 565 95.2 108 13.5

2-25 283.8 595 565 95.2 107.8 13

2-31 283.8 605 595 95.2 105.4 10.5

2-33 283.8 600 570 95.2 108.5 14

2-39 283.8 595 565 95.2 108.2 13.5

2-45 283.8 595 570 95.2 108.2 13.5

2-50 283.8 595 580 95.2 107.5 13

† Sample broke outside the gauge length.

‡ Results not available due to a computer crash.

B1.2


Sample 2 – Round Bar (continued)

Sample Number

Final Diameter (mm)

% Reduction in Area

2-7 12.9 54

2-11 12.8 54.5

2-14 13 53

2-23 13 53

2-25 12.9 54

2-31 13 53

2-33 12.9 54

2-39 13 53

2-45 13 53

2-50 12.8 54.5

Analysis of this testing data indicated that the samples were sufficiently homogeneous for the program and, therefore, any participant results identified as outliers cannot be attributed to sample variability.

APPENDIX C

Instructions to Participants

and

Results Sheet

C1.1

Tensile Testing of Metals, Round 7 December 2014 Page 1 of 3

PROFICIENCY TESTING AUSTRALIA

Tensile Testing Of Metals Proficiency Testing Program

Round 7, December 2014

Instructions To Participants

To ensure that the results of this program can be analysed correctly, participants are asked to note carefully: 1) The samples for this tensile testing program comprise of a steel flat bar sample,

labelled 1-x, and a steel round bar sample, labelled 2-x. 2) The tests to be performed in this program are:

0.2% Proof Stress (non-proportional elongation) (Rp0.2);

Tensile Strength (Rm);

Percentage Elongation after Fracture (A%); and

Percentage Reduction in Area after Fracture (Z%).

3) Tests may commence as soon as samples are received. The samples are to be treated in the same manner as routinely tested samples.

4) All testing, recording and reporting is to be performed in accordance with your routine test methods, but testing in accordance with AS 1391 – Metallic materials – Tensile testing at ambient temperature (2007) or ISO 6892-1 – Metallic materials – Tensile testing – Part 1: Method of test at room temperature (2009) are the preferred test methods.

5) Report only one result per sample, based on the determination for each

property. For each determination, results are to be reported to the accuracy and in the units indicated on the Results Sheet.

6) The method of testing used should also be reported on the Results Sheet (e.g.

AS 1391, ISO 6892-1, etc.)

7) Testing for Percentage Reduction in Area after Fracture (Z%) is to be performed on Sample 2-x only.

C1.2


8) The Percentage Elongation after Fracture (A%) results will be converted by

Proficiency Testing Australia to a proportional gauge length before analysis. Participants should therefore report the Tensile Specimen Width, Tensile Specimen Gauge Length and Tensile Specimen Thickness or Diameter.

9) Participants are also requested to calculate and report an estimate of uncertainty of measurement for each reported measurement result. All estimates of uncertainty of measurement must be given as a 95% confidence

interval (coverage factor k 2). 10) For this program, your laboratory has been allocated the code number on the

attached Results Sheet. All reference to your laboratory in reports associated with this program will be via this code number, ensuring the confidentiality of your results.

11) Return the Results Sheet, either by mail, email or facsimile, to: All results should arrive at the above address by no later than Friday 16

January 2015. Results reported later than this date may not be analysed in the final report.

Mark Bunt Proficiency Testing Australia PO Box 7507 Silverwater NSW 2128 AUSTRALIA

Telephone: + 61 2 9736 8397 (1300 782 867) Fax: +61 2 9743 6664 Email: [email protected]

C2.1


PROFICIENCY TESTING AUSTRALIA

Tensile Testing Of Metals Proficiency Testing Program Round 7, December 2014

RESULTS SHEET

Laboratory Code:

Test Report

results to nearest

Sample 1 Sample 2

Method


0.2% Proof Stress (non-proportional elongation) (Rp0.2)

1 MPa

Tensile Strength (Rm) 1 MPa

Percentage Elongation after Fracture (A%)

1 %

Percentage Reduction in Area after Fracture (Z%)

1%

Where possible, please also report the values for the following:

Test Report

results to nearest

Sample 1 Sample 2


Tensile Specimen Thickness / Diameter

0.01 mm

Tensile Specimen Width 0.01 mm

Tensile Specimen Gauge Length 1 mm

Elastic Stress or Strain Rate number / sec

Plastic Strain Rate number / sec

All estimates of measurement uncertainty (MU) must be given as a 95% confidence

interval (coverage factor k 2). Print Name: _____________________ Signature & Date: ____________________

-----End of Report-----

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